1. Field of the Invention
The invention relates to devices based on surface plasmon polaritons and methods of operating such devices.
2. Discussion of the Related Art
This section introduces aspects that may help facilitate a better understanding of the inventions. Accordingly, the statements of this section are to be read in this light and are not to be understood as admissions about what is in the prior art or what is not in the prior art.
All-optical routers perform optical routing without performing intermediate conversions of received optical signals into electrical signals. Until recently, avoiding such conversions enabled all-optical routers to perform optical routing more rapidly than conventional non-all-optical routers in which received optical signals are converted to intermediate electrical signals. All-optical routers were typically simpler than such non-all-optical routers, because of the absence of hardware for performing such conversions. Indeed, a higher operating speed and a lower complexity often made such all-optical routers preferable to the non-all optical routers.
Recently, interest has increased in various types of non-all-optical routers. One type of non-all-optical router uses surface plasmon polaritons to perform optical routing. This type of non-all-optical router has a potential to both operate at high speeds and be simple and inexpensive to fabricate. In particular, the fabrication of such non-all-optical routers may be largely based on conventional techniques used in micro-electronics and integrated optical fabrication.
Surface plasma polaritons are also commonly referred to as surface plasmons. Surface plasmons are combinations of propagating surface charge densities and associated electromagnetic waves. Surface plasmons can propagate along the interface between a metal and a dielectric and can propagate along the surface of a metal exposed to vacuum. Surface plasmons can propagate along such interfaces and surfaces whether the surfaces are smooth or bumpy and whether the surfaces are flat or curved.